Speed reducer



FIG. 1 is a front view, showing my new speed reducer.

FIG. 2 is a rear view thereof;

FIG. 3 is a left side view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a top view thereof;

FIG. 6 is a bottom view thereof;

FIG. 7 is a first perspective view thereof; and,

FIG. 8 is a second perspective view thereof.

The broken lines in the drawings depict unclaimed environmental subject matter. 

The ornamental design for a speed reducer, as shown and described. 